U.S. patent application number 16/068648 was filed with the patent office on 2019-01-24 for channel assessment method and apparatus, terminal, and base station.
This patent application is currently assigned to Yulong Computer Telecommunication Scientific (Shenzhen) Co., Ltd.. The applicant listed for this patent is Yulong Computer Telecommunication Scientific (Shenzhen) Co., Ltd.. Invention is credited to Mingju Li, Yunfei Zhang, Yajun Zhu.
Application Number | 20190029045 16/068648 |
Document ID | / |
Family ID | 56484193 |
Filed Date | 2019-01-24 |
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United States Patent
Application |
20190029045 |
Kind Code |
A1 |
Li; Mingju ; et al. |
January 24, 2019 |
CHANNEL ASSESSMENT METHOD AND APPARATUS, TERMINAL, AND BASE
STATION
Abstract
A channel assessment method, a channel assessment apparatus, a
terminal and a base station when a LTE system operates in an
unlicensed band are provided, where the method includes: receiving
an uplink scheduling instruction transmitted in a subframe n by a
base station, where the uplink scheduling instruction is configured
to instruct a terminal to transmit uplink data in a subframe n+i by
using an allocated resource; and setting channel assessment time in
a subframe after the subframe n and before the subframe n+i, so as
to detect a clear or busy state of an uplink channel to be occupied
by the terminal.
Inventors: |
Li; Mingju; (Guangdong,
CN) ; Zhu; Yajun; (Guangdong, CN) ; Zhang;
Yunfei; (Guangdong, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Yulong Computer Telecommunication Scientific (Shenzhen) Co.,
Ltd. |
Guangdong |
|
CN |
|
|
Assignee: |
Yulong Computer Telecommunication
Scientific (Shenzhen) Co., Ltd.
Guangdong
CN
|
Family ID: |
56484193 |
Appl. No.: |
16/068648 |
Filed: |
July 30, 2016 |
PCT Filed: |
July 30, 2016 |
PCT NO: |
PCT/CN2016/092468 |
371 Date: |
July 6, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 72/1289 20130101;
H04W 74/0808 20130101; H04W 16/14 20130101; H04W 74/0816 20130101;
H04W 74/08 20130101 |
International
Class: |
H04W 74/08 20060101
H04W074/08; H04W 16/14 20060101 H04W016/14; H04W 72/12 20060101
H04W072/12 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 8, 2016 |
CN |
201610013298.9 |
Claims
1. A channel assessment method when a long term evolution (LTE)
system operates in an unlicensed band, applied in a terminal,
comprising: receiving an uplink scheduling instruction transmitted
by a base station in a subframe n, wherein the uplink scheduling
instruction is configured to instruct the terminal to transmit
uplink data in a subframe n+i by using an allocated resource; and
setting channel assessment time in a subframe after the subframe n
and before the subframe n+i, so as to detect a clear or busy state
of an uplink channel to be occupied by the terminal.
2. The channel assessment method according to claim 1, wherein the
setting channel assessment time in a subframe after the subframe n
and before the subframe n+i comprises: setting a starting point of
the channel assessment time at a starting point of any one subframe
after the subframe n and before the subframe n+i.
3. The channel assessment method according to claim 1, wherein the
setting channel assessment time in a subframe after the subframe n
and before the subframe n+i comprises: setting a starting point of
the channel assessment time at a starting point of a designated
symbol within any one subframe after the subframe n and before the
subframe n+i.
4. The channel assessment method according to claim 3, wherein the
designated symbol comprises: a first symbol within the any one
subframe, a fourth symbol within the any one subframe, a seventh
symbol within the any one subframe, a tenth symbol within the any
one subframe, an eleventh symbol within the any one subframe, a
twelfth symbol within the any one subframe, or a thirteenth symbol
within the any one subframe.
5. The channel assessment method according to claim 1, further
comprising: if it is detected that the uplink channel is in a clear
state before a starting point of the subframe n+i, transmitting an
initial signal or a reservation signal, and occupying the uplink
channel at the starting point of the subframe n+i to transmit the
uplink data; or if it is detected that the uplink channel is in the
clear state before the starting point of the subframe n+i,
performing a self-deferral process, and after the self-deferral
process is performed and before the starting point of the subframe
n+i, performing a channel assessment process for a predetermined
duration; when it is detected that the uplink channel is in the
clear state in the channel assessment process for the predetermined
duration, occupying the uplink channel to transmit the uplink data;
and when it is detected that the uplink channel is in a busy state
in the channel assessment process for the predetermined duration,
not transmitting the uplink data.
6. The channel assessment method according to claim 5, wherein the
predetermined duration is 16 .mu.s+M.times.9 .mu.s, wherein M is
equal to 1 or 2.
7. The channel assessment method according to claim 1, further
comprising: receiving radio resource control (RRC) signaling for
indicating a starting point of the channel assessment time
transmitted by the base station, so as to determine the starting
point of the channel assessment time according to the RRC
signaling; or receiving multiple configuration manners of the
starting point of the channel assessment time and identification
codes corresponding to the configuration manners, which are
transmitted by the base station through the RRC signaling, and
receiving a target identification code transmitted by the base
station through downlink control information (DCI) signaling, so as
to determine the starting point of the channel assessment time
according to a configuration manner corresponding to the target
identification code; or receiving the target identification code
transmitted by the base station through the DCI signaling, so as to
determine the configuration manner corresponding to the target
identification code according to a correspondence between
identification codes and the configuration manners of the starting
point of the channel assessment time, which is stored in the
terminal, and determine the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or listening to signaling, for
indicating that the subframe ends, transmitted by the base station,
so as to determine the starting point of the channel assessment
time according to a last subframe of downlink transmission and the
number of symbols occupied by the last subframe, which are
indicated by the signaling for indicating that the subframe
ends.
8. The channel assessment method according to any one of claims 1
to 1, wherein the value of i is 1, 2, 3, or 4.
9. The channel assessment method according to claim 1, further
comprising: when any one subframe occupies the uplink channel to
transmit the uplink data, indicating that the time starting point
for transmitting the uplink data is the starting point of the any
one subframe and lengths of fourteen symbols or lengths of thirteen
symbols of the any one subframe are continuously occupied.
10. A channel assessment method when a LTE system operates in an
unlicensed band, applied by a base station, comprising:
transmitting an uplink scheduling instruction in a subframe n to a
terminal to instruct the terminal to transmit uplink data in a
subframe n+i by using an allocated resource; and notifying a
starting point of channel assessment time to the terminal, so that
the terminal sets the channel assessment time in a subframe after
the subframe n and before the subframe n+i.
11. The channel assessment method according to claim 10, wherein
the notifying the starting point of channel assessment time to the
terminal comprises: transmitting radio resource control (RRC)
signaling for indicating the starting point of the channel
assessment time to the terminal, so that the terminal determines
the starting point of the channel assessment time according to the
RRC signaling; or transmitting multiple configuration manners of
the starting point of the channel assessment time and
identification codes corresponding to the configuration manners to
the terminal through the RRC signaling, and transmitting a target
identification code to the terminal through a DCI signaling, so
that the terminal determines the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or transmitting the target
identification code to the terminal through the DCI signaling, so
that the terminal determines a configuration manner corresponding
to the target identification code according to a correspondence
between identification codes and the configuration manners of the
starting point of the channel assessment time, which is stored in
the terminal, and determines the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or transmitting signaling for
indicating that the subframe ends to the terminal, wherein the
signaling for indicating that the subframe ends is configured to
indicate a last subframe of downlink transmission and the number of
symbols occupied by the last subframe, so that the terminal
determines the starting point of the channel assessment time
according to the last subframe and the number of symbols occupied
by the last subframe.
12-22. (canceled)
23. A terminal, comprising at least one processor; and a memory
communicably connected with the at least one processor for storing
instructions executable by the at least one processor, wherein the
instructions when executed by the at least one processor causes the
at least one processor to perform: receiving an uplink scheduling
instruction transmitted by a base station in a subframe n, wherein
the uplink scheduling instruction is configured to instruct the
terminal to transmit uplink data in a subframe n+i by using an
allocated resource; and setting channel assessment time in a
subframe after the subframe n and before the subframe n+i, so as to
detect a clear or busy state of an uplink channel to be occupied by
the terminal.
24. A base station, comprising at least one processor; and a memory
communicably connected with the at least one processor for storing
instructions executable by the at least one processor, wherein the
instructions when executed by the at least one processor causes the
at least one processor to perform the channel assessment method
according to claim 10.
25-26. (canceled)
27. The terminal according to claim 23, wherein the the setting
channel assessment time in a subframe after the subframe n and
before the subframe n+i comprises: setting a starting point of the
channel assessment time at a starting point of any one subframe
after the subframe n and before the subframe n+i.
28. The terminal according to claim 23, wherein the setting channel
assessment time in a subframe after the subframe n and before the
subframe n+i comprises: setting a starting point of the channel
assessment time at a starting point of a designated symbol within
any one subframe after the subframe n and before the subframe
n+i.
29. The terminal according to claim 28, wherein the designated
symbol comprises: a first symbol within the any one subframe, a
fourth symbol within the any one subframe, a seventh symbol within
the any one subframe, a tenth symbol within the any one subframe,
an eleventh symbol within the any one subframe, a twelfth symbol
within the any one subframe, or a thirteenth symbol within the any
one subframe.
30. The terminal according to claim 23, wherein the instructions
when executed by the at least one processor further causes the at
least one processor to perform: if it is detected that the uplink
channel is in a clear state before a starting point of the subframe
n+i, transmitting an initial signal or a reservation signal, and
occupying the uplink channel at the starting point of the subframe
n+i to transmit the uplink data; or if it is detected that the
uplink channel is in the clear state before the starting point of
the subframe n+i, performing a self-deferral process, and after the
self-deferral process is performed and before the starting point of
the subframe n+i, performing a channel assessment process for a
predetermined duration; when it is detected that the uplink channel
is in the clear state in the channel assessment process for the
predetermined duration, occupying the uplink channel to transmit
the uplink data; and when it is detected that the uplink channel is
in a busy state in the channel assessment process for the
predetermined duration, not transmitting the uplink data.
31. The terminal according to claim 30, wherein the predetermined
duration is 16 .mu.s+M.times.9 .mu.s, wherein M is equal to 1 or
2.
32. The terminal according to claim 23, wherein the instructions
when executed by the at least one processor further causes the at
least one processor to perform: receiving radio resource control
(RRC) signaling for indicating a starting point of the channel
assessment time transmitted by the base station, so as to determine
the starting point of the channel assessment time according to the
RRC signaling; or receiving multiple configuration manners of the
starting point of the channel assessment time and identification
codes corresponding to the configuration manners, which are
transmitted by the base station through the RRC signaling, and
receiving a target identification code transmitted by the base
station through downlink control information (DCI) signaling, so as
to determine the starting point of the channel assessment time
according to a configuration manner corresponding to the target
identification code; or receiving the target identification code
transmitted by the base station through the DCI signaling, so as to
determine the configuration manner corresponding to the target
identification code according to a correspondence between
identification codes and the configuration manners of the starting
point of the channel assessment time, which is stored in the
terminal, and determine the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or listening to signaling, for
indicating that the subframe ends, transmitted by the base station,
so as to determine the starting point of the channel assessment
time according to a last subframe of downlink transmission and the
number of symbols occupied by the last subframe, which are
indicated by the signaling for indicating that the subframe
ends.
33. The terminal according to claim 23, wherein the instructions
when executed by the at least one processor further causes the at
least one processor to perform: when any one subframe occupies the
uplink channel to transmit the uplink data, indicating that the
time starting point for transmitting the uplink data is the
starting point of the any one subframe and lengths of fourteen
symbols or lengths of thirteen symbols of the any one subframe are
continuously occupied
Description
[0001] This application claims the priority to the Chinese patent
application No. 201610013298.9, entitled "Channel Assessment Method
and apparatus, Terminal, And Base Station", filed on Jan. 8, 2016
in the Chinese Patent Office, which is hereby incorporated by
reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to the technical field of
communication, and relates to, for example, a channel assessment
method, a channel assessment apparatus and a base station.
BACKGROUND
[0003] At present, the 3rd generation partnership project (3GPP)
proposes the concept of licensed-assisted access (LAA), which uses
an unlicensed spectrum with the help of a licensed spectrum of long
term evolution (LTE). However, when a LTE network uses an
unlicensed band, it is necessary to ensure that a LAA system can
coexist with related access technologies (such as Wi-Fi) on a fair
and friendly basis. However, in the traditional LTE system, there
is no listen before talk (LBT) mechanism to avoid collision. In
order to coexist with the Wi-Fi, a LTE system needs a LBT
mechanism. In this way, if it is detected that a channel is in a
busy state on the unlicensed spectrum, the LTE system cannot occupy
the band. If it is detected that the channel is in a clear state,
the LTE system can occupy the band.
[0004] Based on the above problems, a LBT mechanism of load based
equipment (LBE) is proposed in the related art. The LBT mechanism
of the LBE is cycle-free. As long as a service arrives, a clear
channel assessment (CCA) is triggered.
[0005] For uplink transmission of the LAA system, since the uplink
transmission is based on scheduling, if an uplink grant (UL grant)
is transmitted in a subframe n, then the scheduled user equipment
(UE) may transmit uplink data in a subframe n+i by using a resource
block (RB) indicated in the UL grant.
[0006] Since the uplink transmission of the UE in a subframe n+4 is
performed based on the UL grant transmitted by a base station in
the subframe n, if uplink LBT is based on a load, it is not clear
when the scheduled UE starts uplink CCA, i.e. how to configure a
starting point of the uplink CCA time of the scheduled UE received
the UL grant.
SUMMARY
[0007] The present disclosure proposes a channel assessment
solution when a LTE system operates in an unlicensed band, so that
a terminal can specify a starting point of a load-based CCA time in
scheduling-based uplink transmission, and thus the problem of
higher power consumption caused by blindly performing the CCA by
the terminal can be avoided, and the probability of preempting a
channel by the terminal can be increased.
[0008] According to a first aspect, the present disclosure proposes
a channel assessment method when a long term evolution (LTE) system
operates in an unlicensed band, including:
[0009] receiving an uplink scheduling instruction transmitted by a
base station in a subframe n, where the uplink scheduling
instruction is configured to instruct a terminal to transmit uplink
data in a subframe n+i by using an allocated resource; and setting
channel assessment time in a subframe after the subframe n and
before the subframe n+i, so as to detect a clear or busy state of
an uplink channel to be occupied by the terminal.
[0010] In this technical solution, the channel assessment time is
set in the subframe after the subframe n and before the subframe
n+i, so that the terminal can specify a starting point of a
load-based CCA time in scheduling-based uplink transmission, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0011] Alternatively, the setting channel assessment time in a
subframe after the subframe n and before the subframe n+i
includes:
[0012] setting a starting point of the channel assessment time at a
starting point of any one subframe after the subframe n and before
the subframe n+i.
[0013] Alternatively, the setting channel assessment time in a
subframe after the subframe n and before the subframe n+i
includes:
[0014] setting a starting point of the channel assessment time at a
starting point of a designated symbol within any one subframe after
the subframe n and before the subframe n+i.
[0015] Alternatively, the designated symbol includes a first symbol
within the any one subframe, a fourth symbol within the any one
subframe, a seventh symbol within the any one subframe, a tenth
symbol within the any one subframe, an eleventh symbol within the
any one subframe, a twelfth symbol within the any one subframe, or
a thirteenth symbol within the any one subframe.
[0016] Alternatively, the starting point of the channel assessment
time may be set at a starting point of any one subframe, that is,
the first symbol within the any one subframe; or uplink CCA may be
started when a last subframe transmitted at a downlink (that is, a
downlink ending partial subframe) ends. Because when a structure of
a downlink pilot time slot (DwPTS) is multiplexed by the ending
partial subframe, the third symbol, the sixth symbol, the ninth
symbol, the tenth symbol, the eleventh symbol and the twelfth
symbols may be occupied, the starting point of the channel
assessment time may be set at a starting point of the fourth
symbol, the seventh symbol, the tenth symbol, the eleventh symbol
or the thirteenth symbol of any one subframe.
[0017] Alternatively, the method further includes: if it is
detected that the uplink channel is in a clear state before the
starting point of the subframe n+i, transmitting an initial signal
or a reservation signal, and occupying the uplink channel at the
starting point of the subframe n+i to transmit the uplink data;
or
[0018] if it is detected that the uplink channel is in the clear
state before the starting point of the subframe n+i, performing a
self-deferral process, and after the self-deferral process is
performed and before the starting point of the subframe n+i,
performing a channel assessment process for a predetermined
duration; when it is detected that the uplink channel is in the
clear state in the channel assessment process for the predetermined
duration, occupying the uplink channel to transmit the uplink data;
and when it is detected that the uplink channel is in a busy state
in the channel assessment process for the predetermined duration,
not transmitting the uplink data.
[0019] Alternatively, the predetermined duration is 16 us+M.times.9
us, where M is equal to 1 or 2.
[0020] Alternatively, the method further includes: receiving radio
resource control (RRC) signaling for indicating a starting point of
the channel assessment time transmitted by the base station, so as
to determine the starting point of the channel assessment time
according to the RRC signaling; or
[0021] receiving multiple configuration manners of the starting
point of the channel assessment time and identification codes
corresponding to the configuration manners, which are transmitted
by the base station through the RRC signaling, and receiving a
target identification code transmitted by the base station through
downlink control information (DCI) signaling, so as to determine
the starting point of the channel assessment time according to a
configuration manner corresponding to the target identification
code; or
[0022] receiving the target identification code transmitted by the
base station through the DCI signaling, so as to determine the
configuration manner corresponding to the target identification
code according to a correspondence between identification codes and
the configuration manners of the starting point of the channel
assessment time, which is stored in the terminal, and determine the
starting point of the channel assessment time according to the
configuration manner corresponding to the target identification
code; or
[0023] listening to signaling for indicating that the subframe ends
transmitted by the base station, so as to determine the starting
point of the channel assessment time according to a last subframe
of downlink transmission and the number of symbols occupied by the
last subframe, which are indicated by the signaling for indicating
that the subframe ends.
[0024] In this technical solution, the starting point of the
channel assessment time of the terminal may be set by the base
station through the signaling, that is, the channel assessment time
of the terminal is controlled by the base station, and then the
base station can ensure that the probability of preempting the
channel by the terminal is maximized while making the terminal save
power by setting the channel assessment time of the terminal.
[0025] Alternatively, the value of i is 1, 2, 3, or 4.
[0026] Alternatively, the method further includes: when any one
subframe occupies the uplink channel to transmit the uplink data,
indicating that the time starting point for transmitting the uplink
data is the starting point of any one subframe and lengths of
fourteen symbols or lengths of thirteen symbols of any one subframe
are continuously occupied.
[0027] According to a second aspect, the present disclosure further
proposes a channel assessment method when a LTE system operates in
an unlicensed band, including:
[0028] transmitting an uplink scheduling instruction in a subframe
n to a terminal to instruct the terminal to transmit uplink data in
a subframe n+i by using an allocated resource; and
[0029] notifying a starting point of channel assessment time to the
terminal, so that the terminal sets the channel assessment time in
a subframe after the subframe n and before the subframe n+i.
[0030] In this technical solution, the base station notifies the
terminal of the starting point of the channel assessment time, so
that the terminal can specify a starting point of a load-based CCA
time in scheduling-based uplink transmission, that is, the channel
assessment time of the terminal is limited by the base station, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0031] Alternatively, the notifying the terminal of a starting
point of channel assessment time to the terminal includes:
[0032] transmitting radio resource control (RRC) signaling for
indicating the starting point of the channel assessment time to the
terminal, so that the terminal determines the starting point of the
channel assessment time according to the RRC signaling; or
[0033] transmitting multiple configuration manners of the starting
point of the channel assessment time and identification codes
corresponding to the configuration manners to the terminal through
the RRC signaling, and transmitting a target identification code to
the terminal through a DCI signaling, so that the terminal
determines the starting point of the channel assessment time
according to the configuration manner corresponding to the target
identification code; or
[0034] transmitting the target identification code to the terminal
through the DCI signaling, so that the terminal determines a
configuration manner corresponding to the target identification
code according to a correspondence between identification codes and
the configuration manners of the starting point of the channel
assessment time, which is stored in the terminal, and determines
the starting point of the channel assessment time according to the
configuration manner corresponding to the target identification
code; or
[0035] transmitting signaling for indicating that the subframe ends
to the terminal, wherein the signaling for indicating that the
subframe ends is configured to indicate a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, so that the terminal determines the starting point of the
channel assessment time according to the last subframe and the
number of symbols occupied by the last subframe.
[0036] According to a third aspect, the present disclosure further
proposes a channel assessment apparatus when a LTE system operates
in an unlicensed band, including:
[0037] a reception unit, which is configured to receive an uplink
scheduling instruction transmitted by a base station in a subframe
n, where the uplink scheduling instruction is configured to
instruct a terminal to transmit uplink data in a subframe n+i by
using an allocated resource; and
[0038] a channel assessment unit, which is configured to set
channel assessment time in a subframe after the subframe n and
before the subframe n+i, so as to detect a clear or busy state of
an uplink channel to be occupied by the terminal.
[0039] In this technical solution, the channel assessment time is
set in the subframe after the subframe n and before the subframe
n+i, so that the terminal can specify a starting point of a
load-based CCA time in scheduling-based uplink transmission, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0040] Alternatively, the channel assessment unit includes a first
setting subunit, which is configured to set a starting point of the
channel assessment time at a starting point of any one subframe
after the subframe n and before the subframe n+i.
[0041] Alternatively, the channel assessment unit includes a second
setting subunit, which is configured to set the starting point of
the channel assessment time at a starting point of a designated
symbol within any one subframe after the subframe n and before the
subframe n+i.
[0042] Among them, the designated symbol includes a first symbol
within the any one subframe, a fourth symbol within the any one
subframe, a seventh symbol within the any one subframe, a tenth
symbol within the any one subframe, an eleventh symbol within the
any one subframe, a twelfth symbol within the any one subframe, and
a thirteenth symbol within the any one subframe.
[0043] Alternatively, the starting point of the channel assessment
time may be set at a starting point of any one subframe, that is,
the first symbol within any one subframe; or uplink CCA may be
started when a last subframe transmitted at a downlink (that is, a
downlink ending partial subframe) ends. Because when a structure of
a downlink pilot time slot (DwPTS) is multiplexed by the ending
partial subframe, the third symbol, the sixth symbol, the ninth
symbol, the tenth symbol, the eleventh symbol and the twelfth
symbols may be occupied, the starting point of the channel
assessment time may be set at a starting point of the fourth
symbol, the seventh symbol, the tenth symbol, the eleventh symbol
or the thirteenth symbol of any one subframe.
[0044] Alternatively, the apparatus further includes a first
processing unit or second processing unit;
[0045] where the first processing unit is configured to: transmit
an initial signal or a reservation signal if it is detected that
the uplink channel is in a clear state before the starting point of
the subframe n+i, and occupy the uplink channel at the starting
point of the subframe n+i to transmit the uplink data;
[0046] the second processing unit is configured to: perform a
self-deferral process if it is detected that the uplink channel is
in the clear state before the starting point of the subframe n+i,
and after the self-deferral process is performed and before the
starting point of the subframe n+i, perform a channel assessment
process for a predetermined duration; and occupy the uplink channel
to transmit the uplink data when it is detected that the uplink
channel is in the clear state in the channel assessment process for
the predetermined duration, and not transmit the uplink data when
it is detected that the uplink channel is in a busy state in the
channel assessment process for the predetermined duration.
[0047] Alternatively, the predetermined duration is 16 us+M.times.9
us, where M is equal to 1 or 2.
[0048] Alternatively, the apparatus further includes:
[0049] a first reception unit, which is configured to receive radio
resource control (RRC) signaling for indicating a starting point of
the channel assessment time transmitted by the base station, so as
to determine a starting point of the channel assessment time
according to the RRC signaling; or
[0050] a second reception unit, which is configured to receive
multiple configuration manners of the starting point of the channel
assessment time and identification codes corresponding to the
configuration manners, which are transmitted by the base station
through the RRC signaling, and receive a target identification code
transmitted by the base station through downlink control
information (DCI) signaling, so as to determine the starting point
of the channel assessment time according to a configuration manner
corresponding to the target identification code; or
[0051] a third reception unit, which is configured to receive the
target identification code transmitted by the base station through
the DCI signaling, so as to determine the configuration manner
corresponding to the target identification code according to a
correspondence between identification codes and the configuration
manners of the starting point of the channel assessment time, which
is stored in the terminal, and determine the starting point of the
channel assessment time according to the configuration manner
corresponding to the target identification code; or
[0052] a listening unit, which is configured to listen to signaling
for indicating that the subframe ends transmitted by the base
station, so as to determine the starting point of the channel
assessment time according to a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, which are indicated by the signaling indicating that the
subframe ends.
[0053] In this technical solution, the starting point of the
channel assessment time of the terminal may be set by the base
station through the signaling, that is, the channel assessment time
of the terminal is controlled by the base station, and then the
base station may ensure that the probability of preempting the
channel by the terminal is maximized while making the terminal save
power by setting the channel assessment time of the terminal.
[0054] Alternatively, the value of i is 1, 2, 3, or 4.
[0055] Alternatively, the apparatus further includes:
[0056] a data transmission unit, which is configured to indicate
that the time starting point for transmitting the uplink data is
the starting point of any one subframe and lengths of fourteen
symbols or lengths of thirteen symbols of the any one subframe are
continuously occupied, when the any one subframe occupies the
uplink channel to transmit the uplink data.
[0057] According to a fourth aspect, the present disclosure further
proposes a channel assessment apparatus when a LTE system operates
in an unlicensed band, including:
[0058] a transmission unit, which is configured to transmit an
uplink scheduling instruction to a terminal in a subframe n to
instruct the terminal to transmit uplink data in a subframe n+i;
and
[0059] a notification unit, which is configured to notify a
starting point of channel assessment time to the terminal, so that
the terminal sets the channel assessment time in a subframe after
the subframe n and before the subframe n+i.
[0060] In this technical solution, the base station notifies the
terminal of the starting point of the channel assessment time, so
that the terminal can specify a starting point of a load-based CCA
time in scheduling-based uplink transmission, that is, the channel
assessment time of the terminal is limited by the base station, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0061] Alternatively, the notification unit is configured to:
[0062] transmit a radio resource control (RRC) signaling for
indicating the starting point of the channel assessment time to the
terminal, so that the terminal determines the starting point of the
channel assessment time according to the RRC signaling; or
[0063] transmit multiple configuration manners of the starting
point of the channel assessment time and identification codes
corresponding to the configuration manners to the terminal through
the RRC signaling, and transmit a target identification code to the
terminal through a DCI signaling, so that the terminal determines
the starting point of the channel assessment time according to a
configuration manner corresponding to the target identification
code; or
[0064] transmit the target identification code to the terminal
through the DCI signaling, so that the terminal determines the
configuration manner corresponding to the target identification
code according to a correspondence between identification codes and
the configuration manners of the starting point of the channel
assessment time, which is stored in the terminal, and determines
the starting point of the channel assessment time according to the
configuration manner corresponding to the target identification
code; or
[0065] transmit signaling for indicating that the subframe ends to
the terminal, wherein the signaling for indicating that the
subframe ends is configured to indicate a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, so that the terminal determines the starting point of the
channel assessment time according to the last subframe and the
number of symbols occupied by the last subframe.
[0066] According to a fifth aspect, the present disclosure further
provides a terminal, including the channel assessment apparatus
when a LTE system operates in an unlicensed band as described above
in the third aspect.
[0067] According to a sixth aspect, the present disclosure further
proposes a base station, including the channel assessment apparatus
when a LTE system operates in an unlicensed band as described above
in the fourth aspect.
[0068] According to a seventh aspect, the present disclosure
further provides a non-transitory computer-readable storage medium
which is configured in a terminal side and stores
computer-executable instructions, where the computer-executable
instructions may be configured to instruct the channel assessment
method when a LTE system operates in an unlicensed band as
described above in the first aspect.
[0069] According to an eighth aspect, the present disclosure
further provides a non-transitory computer-readable storage medium
which is configured in a base station side and stores
computer-executable instructions, where the computer-executable
instructions may be configured to instruct the channel assessment
method when a LTE system operates in an unlicensed band as
described above in the second aspect.
[0070] Through the above technical solution, the terminal can
specify a starting point of a load-based CCA time in
scheduling-based uplink transmission, and thus the problem of
higher power consumption caused by blindly performing the CCA by
the terminal can be avoided, and the probability of preempting a
channel by the terminal can be increased.
DESCRIPTION OF DRAWINGS
[0071] FIG. 1 shows a schematic flow diagram of a channel
assessment method when a LTE system operates in an unlicensed band
according to a first embodiment of the present disclosure;
[0072] FIG. 2 shows a schematic block diagram showing a channel
assessment apparatus when a LTE system operates in an unlicensed
band according to a first embodiment of the present disclosure;
[0073] FIG. 3 shows a schematic block diagram showing a hardware
structure of a terminal according to an embodiment of the present
disclosure;
[0074] FIG. 4 shows a schematic flow diagram of a channel
assessment method when a LTE system operates in an unlicensed band
according to a second embodiment of the present disclosure;
[0075] FIG. 5 is a schematic block diagram showing a channel
assessment apparatus when a LTE system operates in an unlicensed
band according to a second embodiment of the present
disclosure;
[0076] FIG. 6 shows a schematic block diagram showing a hardware
structure of a base station according to an embodiment of the
present disclosure; and
[0077] FIG. 7 shows a schematic diagram showing a CCA setting
position according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENT
[0078] In order to make the objects, features, and advantages of
the present disclosure be more clearly understood, the present
disclosure will be described below in conjunction with accompanying
drawings and alternative embodiments. It should be noted that
embodiments of the present disclosure and features in the
embodiments may be combined with each other without conflict.
[0079] Many details will be set forth in the following description
in order to provide a thorough understanding of the present
disclosure. However, the present disclosure may also be implemented
in other manners different from those described herein.
Accordingly, a protection scope of the present disclosure is not
limited to specific embodiments disclosed below.
[0080] FIG. 1 shows a schematic flow diagram of a channel
assessment method when a LTE system operates in an unlicensed band
according to a first embodiment of the present disclosure.
[0081] As shown in FIG. 1, a channel assessment method when a LTE
system operates in an unlicensed band according to a first
embodiment of the present disclosure includes: step 102-step
104.
[0082] In step 102, a terminal receives an uplink scheduling
instruction transmitted by a base station in a subframe n, where
the uplink scheduling instruction is configured to instruct a
terminal to transmit uplink data in a subframe n+i by using an
allocated resource.
[0083] In step 104, the terminal sets channel assessment time in a
subframe after the subframe n and before the subframe n+i, so as to
detect a clear or busy state of an uplink channel to be occupied by
the terminal.
[0084] In this technical solution, the terminal sets the channel
assessment time in the subframe after the subframe n and before the
subframe n+i, so that the terminal can specify a starting point of
a load-based CCA time in scheduling-based uplink transmission, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0085] In the above technical solution, alternatively, that the
terminal sets the channel assessment time in a subframe after the
subframe n and before the subframe n+i includes: the terminal sets
the starting point of the channel assessment time at a starting
point of any one subframe after the subframe n and before the
subframe n+i.
[0086] In any one technical solution, alternatively, that the
terminal sets channel assessment time in a subframe after the
subframe n and before the subframe n+i includes:
[0087] the terminal sets the starting point of the channel
assessment time at a starting point of a designated symbol within
any one subframe after the subframe n and before the subframe
n+i.
[0088] The designated symbol may include a first symbol within the
any one subframe, a fourth symbol within the any one subframe, a
seventh symbol within the any one subframe, a tenth symbol within
the any one subframe, an eleventh symbol within the any one
subframe, a twelfth symbol within the any one subframe, or a
thirteenth symbol within the any one subframe.
[0089] Alternatively, the terminal may set the starting point of
the channel assessment time at a starting point of any one
subframe, that is, the first symbol within the any one subframe; or
uplink CCA may be started when a downlink ending partial subframe
ends. Because when a structure of a downlink pilot time slot
(DwPTS) is multiplexed by the ending partial subframe, the terminal
may occupy the third symbol, the sixth symbol, the ninth symbol,
the tenth symbol, the eleventh symbol and the twelfth symbols of
the any one subframe, the terminal may set the starting point of
the channel assessment time at a starting point of the fourth
symbol, the seventh symbol, the tenth symbol, the eleventh symbol
or the thirteenth symbol of the any one subframe.
[0090] In any one technical solution, alternatively, the method may
further include:
[0091] If it is detected that the uplink channel is in a clear
state before the starting point of the subframe n+i, the terminal
transmits an initial signal or a reservation signal, and occupies
the uplink channel at the starting point of the subframe n+i to
transmit the uplink data; or
[0092] if it is detected that the uplink channel is in the clear
state before the starting point of the subframe n+i, the terminal
performs a self-deferral process, and after the self-deferral
process is performed and before the starting point of the subframe
n+i, performs a channel assessment process for a predetermined
duration;
[0093] when it is detected that the uplink channel is in the clear
state in the channel assessment process for the predetermined
duration, the terminal occupies the uplink channel to transmit the
uplink data; and
[0094] when it is detected that the uplink channel is in a busy
state in the channel assessment process for the predetermined
duration, the terminal does not transmit the uplink data.
[0095] Alternatively, the predetermined duration is 16 us+M.times.9
us, where M is equal to 1 or 2.
[0096] In any one technical solution, alternatively, the method may
also include:
[0097] radio resource control (RRC) signaling for indicating a
starting point of the channel assessment time transmitted by the
base station, so as to determine a starting point of the channel
assessment time according to the RRC signaling; or
[0098] multiple configuration manners of the starting point of the
channel assessment time and identification codes corresponding to
the configuration manners, which are transmitted by the base
station through the RRC signaling, are received, and a target
identification code transmitted by the base station through a
downlink control information (DCI) signaling is received, so as to
determine the starting point of the channel assessment time
according to the configuration manner corresponding to the target
identification code; or
[0099] the target identification code transmitted by the base
station through the DCI signaling is received, and the
configuration manner corresponding to the target identification
code is determined according to a correspondence between
identification codes and the configuration manners of the starting
point of the channel assessment time, which is stored in the
terminal, and the starting point of the channel assessment time is
determined according to the configuration manner corresponding to
the target identification code; or
[0100] a signaling, for indicating that the subframe ends,
transmitted by the base station is listened,
[0101] so as to determine the starting point of the channel
assessment time according to a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, which are indicated by the signaling for indicating that
the subframe ends.
[0102] In this technical solution, the starting point of the
channel assessment time of the terminal can be set by the base
station through the signaling, that is, the channel assessment time
of the terminal is controlled by the base station, and then the
base station can ensure that the probability of preempting the
channel by the terminal is maximized while making the terminal save
power by setting the channel assessment time of the terminal.
[0103] In any one technical solution, alternatively, the value of i
is 1, 2, 3, or 4.
[0104] In any one technical solution, alternatively, the method may
also include the following steps.
[0105] When any one subframe occupies the uplink channel to
transmit the uplink data, it is indicated that the time starting
point for transmitting the uplink data is the starting point of any
one subframe and that lengths of fourteen symbols or lengths of
thirteen symbols of the any one subframe are continuously
occupied.
[0106] FIG. 2 shows a schematic block diagram showing a channel
assessment apparatus when a LTE system operates in an unlicensed
band according to a first embodiment of the present disclosure.
[0107] As shown in FIG. 2, a channel assessment apparatus 200 when
a LTE system operates in an unlicensed band according to a first
embodiment of the present disclosure includes a reception unit 202
and a channel assessment unit 204.
[0108] Where the reception unit 202 is configured to receive an
uplink scheduling instruction transmitted by a base station in a
subframe n, where the uplink scheduling instruction is used to
instruct a terminal to transmit uplink data in a subframe n+i by
using an allocated resource.
[0109] The channel assessment unit 204 is configured to set channel
assessment time in a subframe after the subframe n and before the
subframe n+i, so as to detect a clear or busy state of an uplink
channel to be occupied by the terminal.
[0110] In this technical solution, the channel assessment time is
set in the subframe after the subframe n and before the subframe
n+i, so that the terminal can specify a starting point of a
load-based CCA time in scheduling-based uplink transmission, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0111] In the above technical solution, alternatively, the channel
assessment unit 204 may include a first setting subunit 2042, which
is configured to set the starting point of the channel assessment
time at a starting point of any one subframe after the subframe n
and before the subframe n+i.
[0112] In any one technical solution, alternatively, the channel
assessment unit 204 includes a second setting subunit 2044, which
is configured to set the starting point of the channel assessment
time at a starting point of a designated symbol within any one
subframe after the subframe n and before the subframe n+i.
[0113] Herein the designated symbol includes a first symbol within
the any one subframe, a fourth symbol within the any one subframe,
a seventh symbol within the any one subframe, a tenth symbol within
the any one subframe, an eleventh symbol within the any one
subframe, a twelfth symbol within the any one subframe, or a
thirteenth symbol within the any one subframe.
[0114] Alternatively, the starting point of the channel assessment
time may be set at a starting point of any one subframe, that is,
the first symbol within any one subframe; or uplink CCA may be
started when a downlink ending partial subframe ends. Because when
a structure of a downlink pilot time slot (DwPTS) is multiplexed by
the ending partial subframe, the third symbol, the sixth symbol,
the ninth symbol, the tenth symbol, the eleventh symbol and the
twelfth symbols of the any one subframe may be occupied, the
terminal may set the starting point of the channel assessment time
at a starting point of the fourth symbol, the seventh symbol, the
tenth symbol, the eleventh symbol or the thirteenth symbol of the
any one subframe.
[0115] In any one technical solution, alternatively, the apparatus
also includes a first processing unit 206 or second processing unit
208.
[0116] The first processing unit 206 is configured to: if the
channel assessment unit 204 detects that the uplink channel is in a
clear state before the starting point of the subframe n+i, transmit
an initial signal or a reservation signal, and occupy the uplink
channel at the starting point of the subframe n+i to transmit the
uplink data.
[0117] The second processing unit 208 is configured to: if the
channel assessment unit 204 detects that the uplink channel is in
the clear state before the starting point of the subframe n+i,
perform a self-deferral process, and after the self-deferral
process is performed and before the starting point of the subframe
n+i, perform a channel assessment process for a predetermined
duration.
[0118] The second processing unit 208 is configured to when it is
detected that the uplink channel is in the clear state in the
channel assessment process for the predetermined duration, occupy
the uplink channel to transmit the uplink data; and when it is
detected that the uplink channel is in a busy state in the channel
assessment process for the predetermined duration, not transmit the
uplink data.
[0119] Alternatively, the predetermined duration is 16 us+M.times.9
us, where M is equal to 1 or 2.
[0120] In any one technical solution, alternatively, the apparatus
may further include:
[0121] a first reception unit 210, which is configured to receive
radio resource control (RRC) protocol signaling, which is
transmitted by the base station, to indicate a starting point of
the channel assessment time, so as to determine a starting point of
the channel assessment time according to the RRC signaling; or
[0122] a second reception unit 212, which is configured to receive
multiple configuration manners of the starting point of the channel
assessment time and identification codes corresponding to the
configuration manners, which are transmitted by the base station
through the RRC signaling, and receive a target identification code
transmitted by the base station through downlink control
information (DCI) signaling, so as to determine the starting point
of the channel assessment time according to a configuration manner
corresponding to the target identification code; or
[0123] a third reception unit 218, which is configured to receive
the target identification code transmitted by the base station
through the DCI signaling, so as to determine the configuration
manner corresponding to the target identification code according to
a correspondence between identification codes and the configuration
manners of the starting point of the channel assessment time, which
is stored in the terminal, and determine the starting point of the
channel assessment time according to the configuration manner
corresponding to the target identification code; or
[0124] a listening unit 214, which is configured to listen to
signaling for indicating that the subframe ends transmitted by the
base station, so as to determine the starting point of the channel
assessment time according to a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, which are indicated by the signaling indicating that the
subframe ends. In this technical solution, the starting point of
the channel assessment time of the terminal can be set by the base
station through the signaling, that is, the channel assessment time
of the terminal is controlled by the base station, and then the
base station can ensure that the probability of preempting the
channel by the terminal is maximized while making the terminal save
power by setting the channel assessment time of the terminal.
[0125] In any one technical solution, alternatively, the value of i
is 1, 2, 3, or 4.
[0126] In any one technical solution, alternatively, the apparatus
may also include a data transmission unit 216.
[0127] The data transmission unit 216 is configured to: when any
one subframe occupies the uplink channel to transmit the uplink
data, indicate that the time starting point for transmitting the
uplink data is the starting point of any one subframe and lengths
of fourteen symbols or lengths of thirteen symbols of any one
subframe are continuously occupied.
[0128] FIG. 3 shows a schematic block diagram showing a hardware
structure of a terminal according to an embodiment of the present
disclosure.
[0129] As shown in FIG. 3, a terminal 300 according to an
embodiment of the present disclosure may include: one or more
processors 301, where one processor 301 is taken as an example in
FIG. 3; a memory 302.
[0130] The terminal may also include an input apparatus 303 and an
output apparatus 304.
[0131] The processor 301, the memory 302, the input apparatus 303,
and the output apparatus 304 in the terminal may be connected via a
bus or other manners. In FIG. 3, the connection via the bus is
taken as an example.
[0132] The memory 302 as a non-transitory computer-readable storage
medium may be configured for storing software programs,
computer-executable programs, and modules, for example, program
instructions/modules (for example, a reception unit 202 and a
channel assessment unit 204 as shown in FIG. 2) corresponding to
the channel assessment method when a LTE system configured in a
terminal side operates in an unlicensed band in the embodiment of
the present disclosure. The processor 301 is configured to perform
various functional applications and data processing of the server
by running the software programs, the instructions, and the modules
stored in the memory 302, that is, implement the channel assessment
method when the LTE system configured on the terminal side operates
in the unlicensed band in the above method embodiment.
[0133] The memory 302 may include a storage program area and a
storage data area, where the storage program area may store an
operating system, and at least one application required for the
function; the storage data area may store data created according to
the use of a terminal device, and the like. In addition, the memory
302 may include a high-speed random access memory, and may also
include a non-transitory memory, such as at least one disk storage
device, a flash memory device, or other non-volatile solid-state
storage devices. In some embodiments, the memory 302 may optionally
include memories remotely located relative to the processor 301,
and these remotely located memories may be connected to the
terminal device over a network. Examples of such networks include,
but are not limited to, the Internet, intranets, local area
networks, mobile communications networks, and combinations
thereof.
[0134] The input apparatus 303 may be configured to receive input
numeric or character information and generate key signal inputs
related to user's settings and function control of the terminal.
The output apparatus 304 may include a display device such as a
display screen.
[0135] The one or more modules are stored in the memory 302, and
when being executed by the one or more processors 301, perform the
channel assessment method when the LTE system configured on the
terminal side operates in the unlicensed band in the above method
embodiment.
[0136] FIG. 4 shows a schematic flow diagram of a channel
assessment method when a LTE system operates in an unlicensed band
according to a second embodiment of the present disclosure.
[0137] As shown in FIG. 4, a channel assessment method when a LTE
system operates in an unlicensed band according to a second
embodiment of the present disclosure includes: step 402-step
404.
[0138] In step 402, a base station transmits an uplink scheduling
instruction in a subframe n to a terminal to instruct the terminal
to transmit uplink data in a subframe n+i by using an allocated
resource.
[0139] In step 404, the base station notifies the terminal of a
starting point of channel assessment time, so that the terminal
sets the channel assessment time in a subframe after the subframe n
and before the subframe n+i.
[0140] In this technical solution, the base station notifies the
terminal of the starting point of the channel assessment time, so
that the terminal can specify a starting point of a load-based CCA
time in scheduling-based uplink transmission, that is, the channel
assessment time of the terminal is limited by the base station, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0141] In the above technical solution, alternatively, that the
base station notifies the terminal of a starting point of channel
assessment time includes:
[0142] the base station transmits a RRC signaling for indicating
the starting point of the channel assessment time to the terminal,
so that the terminal determines the starting point of the channel
assessment time according to the RRC signaling; or
[0143] the base station transmits multiple configuration manners of
the starting point of the channel assessment time as well as
identification codes corresponding to the configuration manners to
the terminal through the RRC signaling, and transmits a target
identification code to the terminal through a DCI signaling, so
that the terminal determines the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or
[0144] the base station transmits the target identification code to
the terminal through the DCI signaling, so that the terminal
determines the configuration manner corresponding to the target
identification code according to a correspondence between
identification codes and the configuration manners of the starting
point of the channel assessment time, which is stored in the
terminal, and determines the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code; or
[0145] the base station transmits signaling for indicating that the
subframe ends to the terminal, where the signaling for indicating
that the subframe ends is used to indicate the a last subframe of
downlink transmission and the number of symbols occupied by the
last subframe, so that the terminal determines the starting point
of the channel assessment time according to the last subframe and
the number of symbols occupied by the last subframe.
[0146] FIG. 5 is a schematic block diagram showing a channel
assessment apparatus when a LTE system operates in an unlicensed
band according to a second embodiment of the present
disclosure.
[0147] As shown in FIG. 5, a channel assessment apparatus 500 when
a LTE system operates in an unlicensed band according to a second
embodiment of the present disclosure includes a transmission unit
502 and a notification unit 504.
[0148] Where the transmission unit 502 is configured to transmit an
uplink scheduling instruction in a subframe n to a terminal to
instruct the terminal to transmit uplink data in a subframe n+i by
using an allocated resource.
[0149] The notification unit 504 is configured to notify the
terminal of a starting point of channel assessment time, so that
the terminal sets the channel assessment time in a subframe after
the subframe n and before the subframe n+i.
[0150] In this technical solution, the base station notifies the
terminal of the starting point of the channel assessment time, so
that the terminal can specify a starting point of a load-based CCA
time in scheduling-based uplink transmission, that is, the channel
assessment time of the terminal is limited by the base station, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0151] In the above technical solution, alternatively, the
notification unit is configured to:
[0152] transmit a RRC signaling for indicating the starting point
of the channel assessment time to the terminal, so that the
terminal determines the starting point of the channel assessment
time according to the RRC signaling; or
[0153] transmit multiple configuration manners of the starting
point of the channel assessment time and identification codes
corresponding to the configuration manners to the terminal through
the RRC signaling, and transmit a target identification code to the
terminal through a DCI signaling, so that the terminal determines
the starting point of the channel assessment time according to a
configuration manner corresponding to the target identification
code; or
[0154] transmit the target identification code to the terminal
through the DCI signaling, so that the terminal determines the
configuration manner corresponding to the target identification
code according to a correspondence between identification codes and
the configuration manners of the starting point of the channel
assessment time, which is stored in the terminal, and determines
the starting point of the channel assessment time according to the
configuration manner corresponding to the target identification
code; or
[0155] transmit signaling for indicating that the subframe ends to
the terminal, where the signaling for indicating that the subframe
ends is configured to indicate a last subframe of downlink
transmission and the number of symbols occupied by the last
subframe, so that the terminal determines the starting point of the
channel assessment time according to the last subframe and the
number of symbols occupied by the last subframe.
[0156] FIG. 6 shows a schematic block diagram showing a hardware
structure of a base station according to an embodiment of the
present disclosure.
[0157] As shown in FIG. 6, a base station 600 according to an
embodiment of the present disclosure may include: one or more
processors 601, where one processor 601 is taken as an example in
FIG. 6; a memory 602.
[0158] The base station may also include an input apparatus 603 and
an output apparatus 604.
[0159] The processor 601, the memory 602, the input apparatus 603,
and the output apparatus 604 in the base station may be connected
via a bus or other manners. In FIG. 6, the connection through the
bus is taken as an example.
[0160] The memory 602 as a non-transitory computer-readable storage
medium may be configured for storing software programs,
computer-executable programs, and modules, for example, program
instructions/modules (for example, a transmission unit 502 and a
notification unit 504 as shown in FIG. 5) corresponding to the
channel assessment method when a LTE system configured in a base
station side operates in an unlicensed band in the embodiment of
the present disclosure. The processor 601 is configured to perform
various functional applications and data processing of the server
by running the software programs, the instructions, and the modules
stored in the memory 602, that is, implements the channel
assessment method when the LTE system configured on the base
station side operates in the unlicensed band in the above method
embodiment.
[0161] The memory 602 may include a storage program area and a
storage data area, where the storage program area may store an
operating system, and at least one application required for the
function; the storage data area may store data created according to
the use of a terminal device, and the like. In addition, the memory
602 may include a high-speed random access memory, and may also
include a non-transitory memory, such as at least one disk storage
device, a flash memory device, or other non-volatile solid-state
storage devices. In some embodiments, the memory 602 may optionally
include memories remotely located relative to the processor 601,
and these remotely located memories may be connected to the
terminal device over a network. Examples of such networks include,
but are not limited to, the Internet, intranets, local area
networks, mobile communications networks, and combinations
thereof.
[0162] The input apparatus 603 may be configured to receive input
numeric or character information and generate key signal inputs
related to user's settings and function control of the terminal.
The output apparatus 604 may include a display device such as a
display screen.
[0163] The one or more modules are stored in the memory 602, and
when being executed by the one or more processors 601, perform the
channel assessment method when the LTE system configured on the
base station side operates in the unlicensed band in the above
method embodiment.
[0164] In summary, a technical solution of the present disclosure
is mainly directed to a configuration of a starting point of a CCA
time, which is regarding a physical uplink shared channel (PUSCH)
of scheduled UE received a UL grant, and a solution of the proposed
configuration is as follows.
[0165] I. The scheduled UE receives the UL grant in a subframe n,
and a starting point of an uplink CCA time is located after a
subframe n and before a starting boundary of a subframe n+i. That
is, the starting point of the uplink CCA time is set after an
ending boundary of the subframe n and before the starting boundary
of the subframe n+i, where the i may be 1, 2, 3, or 4.
[0166] As shown in FIG. 7, if the i is equal to 4, the time of the
CCA may be set within any one subframe after the subframe n and
before a subframe n+4. Here are a few alternative examples.
[0167] 1. The starting point of the CCA is configured at time
immediately after the UL grant is received, for instance, the CCA
is started at a starting boundary of a subframe n+1 when the
subframe n receives the UL grant.
[0168] 2. The CCA is started at a starting boundary of a subframe
n+2.
[0169] 3. The CCA is started at a starting boundary of a subframe
n+3. This situation represents that a load-based CCA process is of
up to 1 ms.
[0170] 4. The CCA is started at a starting boundary of a m.sup.th
symbol of the subframe n+1 or the subframe n+2 or the subframe n+3,
where m is 1, 4, 7, 10, 11, 12, and 13 (it should be noted that the
number of the m.sup.th symbol in the subframe is m-1), m of 1 means
that it starts from a starting point of the subframe, and other
values of m refer to the number of symbols of multiple structures
of a DwPTS multiplexed by an ending partial subframe, that is, the
uplink CCA may be started when a downlink ending partial subframe
ends. Alternatively, because when the structure of the downlink
pilot time slot (DwPTS) is multiplexed by the ending partial
subframe, the third symbol, the sixth symbol, the ninth symbol, the
tenth symbol, the eleventh symbol and the twelfth symbols within
any one subframe may be occupied, the starting point of the channel
assessment time may be set at a starting point of the fourth
symbol, the seventh symbol, the tenth symbol, the eleventh symbol
or the thirteenth symbol of the any one subframe.
[0171] II. If it is detected that a channel is in a clear state
before the starting boundary of the subframe n+i, an initial signal
or a reservation signal is transmitted, and a PUSCH is started to
be transmitted at the starting point of the n+i; or
[0172] if it is detected that the channel is in the clear state
before the starting boundary of the subframe n+i, a self-deferral
process is performed, and then a CCA up to 16 us+M.times.9 ms is
performed before the starting boundary of the subframe n+i, where M
is equal to 1 or 2, and if it is detected that the channel is in
the clear state, uplink data is transmitted, and if it is detected
that the channel is busy, the uplink data is not transmitted.
[0173] III. A configuration signaling of a starting point of a
CCA
[0174] 1. A configuration through a RRC signaling: this case is
applicable to a semi-static configuration of a starting point of a
CCA time, for instance, is fixed at the beginning of a symbol of a
subframe n+1 or n+2 or n+3.
[0175] 2. A RRC signaling and a DCI signaling: this case is
applicable to a dynamic configuration of a starting point of a CCA
time. For instance, it is not determined that it starts from which
symbol of which subframe, there is a need for the DCI signaling to
indicate it. Alternatively, the RRC signaling gives multiple
possible configurations and bit sequences of DCI, corresponding to
the configurations, and the DCI signaling gives a bit sequence.
After the user receives the RRC signaling and the DCI signaling,
that is, the configuration of the starting point of the CCA time is
known. In addition, it should be noted that if the starting point
of the CCA time is configured at a certain symbol of the subframe
n+3, a DCI signaling needs to be transmitted in the subframe n+2,
and the subframe n+3 may need to transmit the same DCI signaling
again. Such a manner of multiple transmissions may ensure that the
UE receives the DCI signaling and avoids the problem that some UEs
do not receive the DCI signaling.
[0176] As one embodiment rather than a limitation, various possible
configurations and bit sequences of the DCI signaling,
corresponding to the configurations, which are included in the RRC
signaling, may be as shown in Table 1:
TABLE-US-00001 TABLE 1 Bit sequence of DCI Configuration of
starting point of CCA 0000 Configuration 1 Start at a first symbol
of the next subframe 0001 Configuration 2 Start at a fourth symbol
of the next subframe 0010 Configuration 3 Start at a seventh symbol
of the next subframe 0011 Configuration 4 Start at a tenth symbol
of the next subframe 0100 Configuration 5 Start at an eleventh
symbol of the next subframe starts 0101 Configuration 6 Start at a
twelfth symbol of the next subframe 0110 Configuration 7 Start at a
thirteenth symbol of the next subframe 0111 Configuration 8 Start
at a first symbol of a current subframe 1000 Configuration 9 Start
at a fourth symbol of a current subframe 1001 Configuration 10
Start at a seventh symbol of a current subframe 1010 Configuration
11 Start at a tenth symbol of a current subframe 1011 Configuration
12 Start at an eleventh symbol of a current subframe 1100
Configuration 13 Start at a twelfth symbol of a current subframe
1101 Configuration 14 Start at a thirteenth symbol of a current
subframe 1110 Reserved 1111 Reserved
[0177] As shown in Table 1, the DCI signaling transmits a bit
sequence 0011 in a subframe n+2, which indicates that UE is
informed to start a CCA at the 10th symbol of the subframe n+3. The
DCI signaling may be transmitted on an unlicensed spectrum by using
a PDCCH (Physical Downlink Control Channel) common signaling,
particularly, using a DCI format 1C or 1A.
[0178] 3. A correspondence between multiple configurations, which
are transmitted by the RRC signaling, of the starting point and
corresponding identification codes of DCI in the foregoing 2 may be
directly stored in a chip of the terminal instead of being
transmitted by using the RRC signaling. Only the DCI signaling
needs to be transmitted to the terminal to indicate a target
identification code, so that the terminal may determine the
configuration manner corresponding to the target identification
code according to a correspondence (which may be a table) between
identification codes and the configuration manners of the starting
point of the channel assessment time, which is stored in the
terminal, and determine the starting point of the channel
assessment time according to the configuration manner corresponding
to the target identification code.
[0179] 4. An existing signaling used to indicate an ending partial
subframe is directly multiplexed, and no additional signaling
indication is needed. Then, it is necessary to define a behavior of
the scheduled UE: after receiving the UL grant, the scheduled UE
shall listen to a signaling, which is transmitted by the base
station, to indicate a structure of the ending partial subframe,
the signaling is transmitted by the PDCCH common signaling, that
is, it indicates which subframe is the last subframe transmitted by
a downlink, and also indicates which DwPTS structure is used by the
subframe, i.e. how many symbols are occupied. Then, the starting
point of the CCA time of the UE starts at the beginning of the next
symbol after the number of symbols occupied by the ending partial
subframe ends, for instance, the ending partial subframe occupies 3
symbols, and the starting point of the CCA time starts from the
fourth symbol.
[0180] The above technical solution of the present disclosure
proposes a method for configuring a starting point of uplink CCA
time and relevant signaling instructions to explicitly inform the
scheduled UE to detect relevant signalings after receiving the UL
grant, obtain the configuration information about a time starting
position of the CCA and enable the CCA according to the
configuration information, so that the time of performing uplink
channel assessment by the UE is controlled by the base station, the
power saving of the terminal is achieved and the probability of
preempting the channel by the terminal is maximized.
[0181] An embodiment of the present disclosure provides a
non-transitory computer-readable storage medium which is configured
in a terminal side and is configured to store computer-executable
instructions, where these computer-executable instructions are
configured to perform the channel assessment method when a LTE
system configured in a terminal side operates in an unlicensed band
according to any one of the foregoing items.
[0182] An embodiment of the present disclosure provides a
non-transitory computer-readable storage medium which is configured
in a base station side and is configured to store
computer-executable instructions, where these computer-executable
instructions are configured to perform the channel assessment
method when a LTE system configured in a base station side operates
in an unlicensed band according to any one of the foregoing
items.
[0183] The technical solution of the present disclosure has been
described in detail above with reference to the accompanying
drawings. The present disclosure proposes a novel channel
assessment solution when a LTE system operates in an unlicensed
band, so that a terminal can specify a starting point of a
load-based CCA time in scheduling-based uplink transmission, and
thus the problem of higher power consumption caused by blindly
performing the CCA by the terminal can be avoided, and the
probability of preempting a channel by the terminal can be
increased.
[0184] The foregoing descriptions are merely exemplary embodiments
of the present disclosure and are not intended to limit the present
disclosure. For those skilled in the art, the present disclosure
may have various changes and modifications. Any modifications,
equivalent substitutions, or improvements made within the spirit
and principle of the present disclosure shall fall within the
protective scope of the present disclosure.
INDUSTRIAL APPLICABILITY
[0185] A technical solution of the present disclosure ensures that
a terminal can specify a starting point of a load-based CCA time in
scheduling-based uplink transmission, and thus the problem of
higher power consumption caused by blindly performing the CCA by
the terminal can be avoided, and the probability of preempting a
channel by the terminal can be increased.
* * * * *